If you were to try to picture an apple right now, can you see it? The shape, the color, the skin, the stem? Or is there no ...

But there are some people who simply cannot form such mental images. They have a condition known as aphantasia, or “mind blindness”—it’s rare, and only affects about 4 percent of the ...

For most of us that's a natural and easy thing to do. But if you have aphantasia you'd find that very difficult, probably even impossible. The condition didn’t even have a name until 2015 ...